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APPENDIX B: ALTITUDE CORRECTION
CO2 sensor modules are calibrated at sea level
and are not designed to automatically
compensate for changes to CO2 at higher
altitudes.
The CO2 level will be approximately 3% lower for
every increase of 1,000 feet (300m) in altitude.
For example, at 5,000 feet a meter reading 400
ppm calibrated at sea level would read
approximately 340 ppm.
Rather than making this calculation each time you use the monitor, you can look up your
location’s altitude online and enter the closest value into the monitor’s menu settings. Then the
calculation will be made automatically before the CO2 level on the LCD is displayed.
Here is a list of the 8 largest cities in the US, and the elevation measured at their airport.
City
Airport where
measured
Elevation
(nearest 50 ft.)
Set monitor
elevation to
Los Angeles, CA
LAX
150 ft.
0 ft.
Chicago, IL
MDW
600 ft.
500 ft.
Houston, TX
IAH
100 ft.
0 ft.
Philadelphia, PA
PHL
0 ft.
0 ft.
Phoenix, AZ
PHX
1150 ft.
1000 ft.
San Antonio, TX
SAT
800 ft.
1000 ft.
San Diego, CA
SAN
0 ft.
0 ft.
Dallas, TX
DFW
600 ft.
500 ft.
List of major cities worldwide by elevation:
https://en.wikipedia.org/wiki/List_of_cities_by_elevation
